This invention relates to a dispenser assembly through which semi-liquid manure is expelled from the spreader onto a field. The spreader with which the dispenser assembly is used has an open topped tank allowing use of power loading equipment. Texture of the manure varies from a slurry to a semi-solid containing fibrous vegetable matter. It is important that the distribution pattern from the spreader be even across the field for a continuum of spread rate conditions.
Several manure spreading machines exist in the art. Some are designed for spreading liquid manures. Others are designed for spreading fibrous manure solids. The U.S. Pat. No. to Vaughn (3,420,452) shows one approach for handling liquid manure. Vaughan discloses a cylindrical tank supported on its side by a tractor drawn trailer. The power takeoff from the tractor is coupled to a shaft which penetrates the front end of the tank near the bottom. The shaft runs the length of the tank leaving at the lower rear wall where it serves as the drive for a centrifugal pump. That portion of the shaft on the inside of the tank includes an auger mechanism for continuously stirring the liquid manure slurry. The tank is filled by means of a hatch on the top. A discharge port near the bottom of the rear wall of the tank allows liquid manure to enter the centrifugal pump. The blades of the impeller fling the manure slurry a considerable distance in an arc away from the aperture in the pump housing.
My copending application having Ser. No. 372,423, now abandoned, describes a flail auger assembly for a spreader of the same general configuration as that on which this invention is implemented. The spreader has an open topped V-shaped tank supported on a tractor drawn trailer. The power takeoff of the tractor is coupled to a shaft which penetrates the front end of the tank near the bottom of the converging generally V-shaped sides. The shaft continues the length of the tank exiting near the bottom of the rear wall where it serves as the drive for the expeller pump.
The V-Model spreader produced by Martin Manufacturing Company of Myerstown, Pa. discloses a prior art approach for gating semi-liquid manure into the expeller pump. There is a hydraulically actuated sliding gate between the end of the tank and the expeller pump. The gate comprises two flat plates, each of which has a semicircular notch along its innermost edge. In the closed position, the plates abut the central shaft of the pump, thereby stopping flow of the slurry-like manure into the pump. The gate is opened by sliding the plates endwise away from each other along slots. The rate of flow from tank to pump is thus a function of the amount of separation between plates. Control of flow into the expeller pump in this manner results in variations in spread patterns of manure onto the field depending on the particle size and slurry consistency.
My invention solves this problem by providing a control gate which is mounted externally at the exit opening of the expeller pump. By moving the gate horizontally across the exit opening, a constant height expeller orifice is maintained. As a result there is a nearly uniform distribution of manure particles out onto the ground along a path of constant width while allowing the size of the gate opening to regulate density of deposition.